Today Recep Tayyip Erdoğan marks his 3,658th day as Turkey’s prime minister, equalling Adnan Menderes’s record. Tomorrow, he assumes Menderes’s spot as Turkey’s third-longest serving prime minister. If he is still in post on Wednesday 14 August 2013, which is likely, Mr Erdoğan will rise to number two.

This is a week for milestones in the incumbent prime minister’s career. Last Thursday he marked ten years since assuming the premiership after winning the Siirt by-election and becoming an MP for the first time.

Adnan Menderes led Turkey’s first opposition party to be elected to office, the Democrat Party. He became prime minister in 1950, leading his party into three successive elections until he was toppled in a coup on 27 May 1960, his own 3,658th day. He was subsequently tried and hanged by the new regime.

Happily for Turkish democracy, Mr Erdoğan’s fate today won’t be the same. But the milestone comes at a time of intense speculation over how long he will be staying in post. Plans of establishing an executive presidency for himself as a side-effect of a possible Kurdish peace deal have been widely reported, although this is unlikely to happen this year, given that a commission charged with writing Turkey’s new constitution is not due to report back until the end of October.

By that time, Mr Erdoğan will have exceeded the 3,805 days cumulatively served as prime minister by Süleyman Demirel. He is expected to lead his party into local elections in March 2014 and the next general election is scheduled for the year after – but a new constitution could bring that forward.

Regardless of when he fights the elections, he will still be some way off reaching the uninterrupted 4,618 days of İsmet İnönü, in post betwen 1925 and 1937. Mr Erdoğan would equal İnönü’s record on 4 November 2015 – but one gets the feeling Turkey will have a different prime minister by then.